Lightweight collapsible stroller

ABSTRACT

A stroller is provided, which includes a frame and a drive mechanism coupled to the frame and configured to transition the frame between an open position and a closed position. The drive mechanism includes: a cable drive; at least one spool rotated by the cable drive; at least one cable received by the at least one spool and connected to the frame; and at least one biasing member connected to the at least one cable for removing slack from the at least one cable. The stroller is configured such that rotation of the at least one spool by the cable drive causes the cable to exert a force against the frame to transition the frame between the open position and the closed position or between the closed position and the open position.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No.13/672,038 filed Nov. 8, 2012, which claims priority to U.S. ProvisionalPatent Application No. 61/557,694 filed on Nov. 9, 2011, the disclosuresof which are hereby incorporated by reference in their entireties.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates generally to strollers, and moreparticularly, to lightweight baby strollers adapted for use duringactive movement such as jogging.

2. Description of Related Art

Baby strollers, also referred to as baby carriages, baby buggies, orprams, have been used to hold and transport babies and young childrenfor many years. Early baby strollers had parts which were fixedlysecured to one another such that they did not fold for compactness. Babystrollers have been designed to have some parts which are movablerelative to one another to allow movement of some parts of the strollerto achieve a more compact configuration when not in use. However,current strollers do not allow for movement or folding to compactconfiguration as desired, and are cumbersome and sometimes difficult tomove between their collapsed (closed) positions and their operative(open) positions, particularly when attending to a baby or child. Morerecently, strollers that automatically transition between theircollapsed and operative positions, such as a stroller that does so uponthe push of a button via motorized movement, have recently been created.

In addition to designing baby strollers that are easily foldable tocompact and transportable configurations, efforts have been directed toreducing the total weight of baby strollers so that the effort requiredto push the stroller is effectively reduced. Lightweight strollers areespecially desirable for use during physically demanding activities suchas pushing the stroller while jogging. In addition, lightweightstrollers are clearly easier to transport (e.g., loading into cars,carrying up stairs) particularly for smaller users. Efforts to reducethe overall weight of a baby stroller include replacing metal structuralmaterials with lightweight structural materials such as hard plastics.In addition, new stroller designs have been proposed which use fewerstructural members, reduce the length and width of frame materials, orwhich replace structural framing materials with tubular hollow framingmaterials. However, lightweight strollers generally lack the improvedfunctionality, structural stability, and stylish design which usersexpect from larger heavier models.

Therefore, a need exists for a lightweight jogging stroller formedsubstantially from lightweight materials such as hard plastics. Thestroller should effectively achieve the functional advantages of heavierstrollers (e.g., automatic folding, full suspension, expansive onboardstorage, electric safety features such as day time running lights,safety sensors, etc.). The stroller should also exhibit good structuralstability and should not bend or pivot when pushed on by a user. Thestability of the device should inspire confidence in users. Alightweight stroller exhibiting at least these features is describedherein.

SUMMARY OF INVENTION

The present invention provides a lightweight stroller which can bequickly and easily transitioned between a closed position and an openposition. The stroller includes a right frame and a left frame. Eachframe has a front support rotatably connected to a rear support at aframe joint. The front support of each frame is a telescoping tubeassembly which includes: an outer tube extending from an end of thefront support to the frame joint of the support; an inner tube assemblypartially inserted within the outer tube and protruding from the outertube; and, a slot extending longitudinally along at least a portion ofthe outer tube. The stroller further includes a linkage comprising atleast two substantially rigid members connected between the right frameand the left frame, the rigid members being connected to the frontsupports at a right slideable joint and a left slidable joint. Thejoints are received within the slot of the outer tube. A drive mechanismcoupled to the right or left frame is also provided. The front supportand the rear support of the right frame and the left frame are movablefrom an open position to a closed position by the drive mechanism. Inaddition, transitioning the stroller from the open position to theclosed position causes the slideable joints to slide downward along theslots of the outer tube.

In certain configurations, the inner tube assembly of the strollerincludes: an inner tube which is inserted partially within the outertube and protrudes from the outer tube at the frame joint; a tubestiffening member inserted within the outer tube and disposed below theslideable joint when the front support is in the open position, the tubestiffener having a slot which corresponds with the slot of the outertube; and, an extension member extending between an end of the innertube which is inserted in the outer tube and the slidable joint.Optionally, the extension member is configured to push the slideablejoint longitudinally through the slot of the tube stiffener and the slotof the outer tube when the stroller transitions from the open positionto the closed position, and the extension member is received within theslot of the tube stiffener. The tube stiffener may further include anunbroken sidewall enclosing a hollow portion extending longitudinallythrough the tube stiffener.

In certain further configurations of the stroller, the drive mechanismincludes a cable drive, a spool rotated by the cable drive, and a cablereceived by the spool, wherein the cable is coupled to the inner tube.The cable drive may be in direct rotational connection with the spool.Preferably, the cable is formed of a synthetic polymer, such as ultrahigh molecular weight polyethylene. The stroller may also include abiasing member connected in series with the cable for removing slackfrom the cable while the drive mechanism is engaged. The drive mechanismmay be powered by a battery, an electrical generator, a spring,compressed air, or any combination thereof.

In certain configurations, the linkage of the stroller is a scissorlinkage configured such that the rigid members are connected between thefront support of one frame and the rear support of the other frame and,wherein the rigid members of the scissor linkage are connected at arotatable center joint such that as the stroller transitions from theopen position to the closed position, the rigid members rotate about thecenter joint bringing ends of the rigid members closer together.Optionally, the stroller also includes an activation button for engagingthe drive mechanism. The activation button may be a dead man switch. Thestroller may further include a screen for presenting information to auser, wherein the information includes air temperature, battery power,time, speed, or distance traveled.

In certain configurations, the stroller further includes a parallelogramlinkage connected between the right frame and the left frame, theparallelogram linkage comprising: a foldable upper horizontal member; afoldable lower horizontal member approximately parallel to the upperhorizontal member; and, a latch, which when engaged, maintains themembers in an extended position and when disengaged permits the membersto fold. In addition, the stroller may further include a parallelogramdrive mechanism coupled to the parallelogram linkage for transitioningthe horizontal members of the parallelogram linkage from the extendedposition to the folded position.

In certain configurations, a storage assembly may be affixed to thestroller. Optionally, the storage assembly includes: a storage bag; atleast one cable fixedly attached to the right frame and at least onecable fixedly attached to the left frame; and a flexible joint forconnecting the cables to the bag. The storage assembly is configuredsuch that the bag remains in an expanded position when the frame movesfrom the open position to the closed position.

In accordance with a further aspect of the present invention, a strolleris provided which includes: a right frame and a left frame, each framecomprising a front support rotatably connected to a rear support at aframe joint; a parallelogram linkage connected between the right frameand the left frame comprising a foldable upper horizontal member, afoldable lower horizontal member approximately parallel to the upperhorizontal member, and, a latch, which when engaged, maintains themembers in an extended position and when disengaged permits the membersto fold; and, a drive mechanism coupled to the frame or parallelogramlinkage. The invented stroller provides that the front support and therear support of the right frame and the left frame are movable from anopen position to a closed position, the horizontal members of theparallelogram linkage transition from the extended position to thefolded position concurrently with the transition of the frame from theopen position to the closed position, and movement of the frames ortransition of the parallelogram linkage is effectuated by the drivemechanism.

In certain configurations, the drive mechanism includes a drive, a gearengaged with and driven by the drive, and a locking member connected tothe gear. Optionally, the locking member engages the upper or lowerhorizontal member of the parallelogram linkage for transitioning theparallelogram linkage from the extended position to the folded position.The drive mechanism includes a manual clutch configured to selectivelyengage and disengage the drive from the gear. Furthermore, the drive maybe configured such that as the drive is being engaged with the gear, thedrive applies a light preload pressure to align the drive and gearbefore a full force of the drive is applied to the gear.

In accordance with a further aspect of the present invention, a strolleris provided which includes a frame moveable from an open position to aclosed position and a drive mechanism coupled to a portion of the frame.The drive mechanism includes: a cable drive; a spool rotated by and indirect rotational connection with the cable drive; a cable received bythe spool; and, a biasing member connected in series with the cable forremoving slack from the cable when the drive mechanism is engaged.

These and other features and characteristics of the present invention,as well as the methods of operation and functions of the relatedelements of structures and the combination of parts and economies ofmanufacture, will become more apparent upon consideration of thefollowing description and the appended claims with reference to theaccompanying drawings, all of which form a part of this specification,wherein like reference numerals designate corresponding parts in thevarious figures. It is to be expressly understood, however, that thedrawings are for the purpose of illustration and description only andare not intended as a definition of the limits of the invention. As usedin the specification and the claims, the singular form of “a”, “an”, and“the” include plural referents unless the context clearly dictatesotherwise.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a forwardly directed perspective view of a collapsiblestroller, according to an embodiment of the present invention, shown inits open position;

FIG. 2 is a front view of the stroller of FIG. 1 shown in its openposition;

FIG. 3 is a rear view of the stroller of FIG. 1 shown in its openposition;

FIG. 4 is a side view of the stroller of FIG. 1 shown in its openposition;

FIG. 5 is a perspective view of the stroller of FIG. 1 shown in itsfully closed position;

FIG. 6 is a front view of the stroller of FIG. 1 shown in its fullyclosed position;

FIG. 7 is a side view of the stroller of FIG. 1 shown in its fullyclosed position;

FIG. 8 is a forwardly directed perspective view of the stroller of FIG.1 having a seat and a storage bag affixed thereto;

FIG. 9 is a rearwardly directed perspective view of the stroller of FIG.1 having a seat and a storage bag attached thereto;

FIG. 10 is a perspective view of the inner tube assembly of the frontsupport of the stroller of FIG. 1;

FIG. 11 is a perspective cross-sectional view of the angled member ofstroller of FIG. 1 with an inner tube nested within an outer tube;

FIG. 12 is a magnified side view of the stroller of FIG. 1 focusing onthe drive mechanism for the frame;

FIG. 13 is a cross-sectional view of the drive mechanism of FIG. 12;

FIG. 14 is a cross-sectional view of the upper portion of the inner tubeof the angled member of the stroller of FIG. 1;

FIG. 15 is a magnified rear view of the stroller of FIG. 1 focusing onthe parallelogram linkage and driving mechanism for the parallelogramlinkage;

FIG. 16 is a magnified cross-sectional view of the drive mechanism forthe foldable linkage of the stroller of FIG. 1 with the horizontalmembers in the extended position;

FIG. 17 is a top view of the stroller of FIG. 1 focusing on the ahandles, activation button, and LCD screen;

FIG. 18 is a magnified view of the LED screen of the stroller of FIG. 1,positioned on the handle bar assembly;

FIG. 19 is a block diagram depicting the activation sequence of thestroller of FIG. 1; and,

FIG. 20 is a block diagram depicting the folding sequence of thestroller of FIG. 1.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

For purposes of the description hereinafter, the terms “upper”, “lower”,“right”, “left”, “vertical”, “horizontal”, “top”, “bottom”, “lateral”,“longitudinal”, and derivatives thereof shall relate to the invention asit is oriented in the drawing figures. However, it is to be understoodthat the invention may assume alternative variations and step sequences,except where expressly specified to the contrary. It is also to beunderstood that the specific devices and processes illustrated in theattached drawings, and described in the following specification, aresimply exemplary embodiments of the invention. Hence, specificdimensions and other physical characteristics related to the embodimentsdisclosed herein are not to be considered as limiting.

With reference to FIGS. 1-9, a stroller 10 includes a right frame 12, aleft frame 14, and a linkage (e.g., a parallelogram linkage 16 and/or ascissor linkage 18) connected therebetween. The frames 12, 14 andlinkage 16, 18 may be formed from any suitable material strong enough tosupport the stroller 10 and occupant including hard plastics and metal.In certain embodiments, the frames 12, 14 are formed from hollow tubularmembers to reduce the weight of the stroller 10.

The right frame 12 and left frame 14 are substantially identical inappearance and construction. The right frame 12 is describedhereinafter. However, it is understood that the left frame 14 isconstructed to mirror the right frame 12. The right frame 12 includes afront support 20 rotatably connected to a rear support 22 at a framejoint 24. The front support 20 and the rear support 22 are moveable froman open position to a closed position. In the open position, the frontsupport 20 is positioned at approximately a 45 degree angle relative tothe rear support 22. In the closed position, the front support 20 andrear support 22 are approximately parallel. However, these angles arenot intended to be limiting and may vary within the scope of the presentinvention. In one exemplary embodiment, the stroller in the openposition is depicted in FIGS. 1-4. The stroller in the closed positionis depicted in FIGS. 5-7.

The linkage connecting the right frame 12 to the left frame 14 may beany suitable structural member including, but not limited to, theparallelogram linkage 16 and/or the scissor linkage 18. In onenon-limiting embodiment, a parallelogram linkage 16 is formed of afoldable upper horizontal member 26 and a foldable lower horizontalmember 28, wherein the members 26, 28 are connected between the rearsupports 22 of the right frame 12 and the left frame 14. The horizontalmembers 26, 28 each include a first section 30 and a second section 32connected by a folding joint 34. The parallelogram linkage 16 furtherincludes a latch 36 engaged with the folding joint 34 which, whenlocked, maintains the horizontal members 26, 28 in an extended positionand which, when released, permits the folding joint 34 to transition tothe folded position. The parallelogram linkage 16 is configured totransition from the extended position to the folded positionconcurrently with the transition of the frames 12, 14 from the openposition to the closed position. A parallelogram linkage 16 containingtwo horizontal members 26, 28 is found to offer advantages compared toother known configurations for connecting frame structures of astroller. Specifically, since the members 26, 28 are relatively smalland since there is a large space between the horizontal members 26, 28and the ground, a user will not kick or bump the linkage 16 whilepushing the stroller 10. In addition, since the parallelogram linkage 16takes up only a small portion of the rear supports 22, there issufficient space to hang storage devices such as bags or panniers off ofthe rear supports 22 without obstructing the folding motion of thelinkage 16. Finally, a linkage 16 comprising two parallel horizontalmembers 26, 28 is generally believed to be visually appealing and lesscluttered than alternative linkage designs which include more parts andfewer straight lines.

In certain embodiments, the stroller 10 further includes the scissorlinkage 18. The scissor linkage 18 includes two substantially rigidmembers 38 connected between a rear support 22 and a front support 20 ofthe opposing frame. The rigid members 38 are connected to the frontsupport 20 at a slideable joint 40 capable of sliding upward anddownward along a lower portion of the front support 20. The slideablejoints 40 are configured to slide downward along the front supports 20concurrently with the transition of the frames 12, 14 from the openposition to the closed position. In certain embodiments, the rigidmembers 38 are connected together at a rotatable center joint 42. Themembers 38 are rotated together around the center joint 42 as the frames12, 14 transition from the open position to the closed position.

The stroller 10 may further include additional elements extending fromthe frames to facilitate pushing the stroller. For example, in certainembodiments, handles 44 extend from the top of the front supports 20 forpushing the stroller.

Additionally, the stroller 10 includes front 46 and rear wheels 48attached to the lower end of the front support 20 and rear supports 22,respectively. In one embodiment, the wheels 46, 48 are connected to theframes 12, 14 through a suspension system for absorbing bumps ordepressions in the ground to make pushing the stroller 10 easier and toimprove ride comfort for the child occupant. The suspension system maybe a spring based suspension system or any other suitable system as isknown in the art.

The stroller 10 may further include a foot stand (not shown) which mayfurther assist in keeping the stroller upright in the folded (e.g.,closed) position. The foot stand may extend between the lower portionsof the front supports 20 and may also house additional electronicfeatures such as day time running lights (not shown).

With reference to FIG. 8, in certain embodiments, the lower portion ofthe front supports 20 may provide an attachment mechanism for a childsupport area including a child seat 50. The child support area may beanchored to the front supports 20 at a position between the slideablejoint 40 and frame joint 24, such that movement of the slideable joint40 is not obstructed by seat 50. A cover or umbrella (not shown) mayalso be connected to the frames 12, 14, for protecting the child fromexposure to the sun. In certain embodiments, the cover (not shown) isconnected to the upper portion of the front supports 20, at a pointabove the frame joint 24.

With reference to FIGS. 8 and 9, a storage bag 70 may be attached to therear supports 22 of the stroller 10. The storage bag can be used tocarry supplies for the child occupant or for the user, such as fooditems, clothing, diapers, toys, etc. With most folding strollers,storage bags are generally folded up in connection with the folding ofthe stroller frame. It was important to remove all items from the bagbefore folding the stroller so that nothing would be damaged.Alternatively, the bag could be removed before folding the stroller.When manually closing a stroller, a user would typically notice ifobjects were still in the bag and could remove the objects or bag fromthe stroller before continuing to fold the stroller. A unique problemwith power folding strollers, such as the stroller 10 of the presentinvention, is that the user may initiate automatic folding of thestroller 10 without realizing that objects are contained within the bag.Since the folding process is automatic, the bag may collapse breakingobjects contained therein, before the user realizes that the bag wasloaded. Therefore, in a preferred and non-limiting embodiment of thepresent invention, the storage bag 70 is configured to remain in anunfolded (e.g., expanded) position while the stroller 10 transitionsbetween the open and closed positions. To maintain the bag 70 in theexpanded position, in one embodiment, the bag 70 further includes cables72 fixedly connected to the frame 12, 14. For example, the cables 72 maybe anchored to the frame joints 24. The cables 72 may be any sort ofwebbing, fabric, or material which is sufficiently strong to support theweight of the bag 70 and objects contained therein. The cables 72 arecoupled to the bag 70 at a flexible joint. The cables 72 and flexiblejoint are configured such that, as shown in FIG. 9, when the stroller 10is in the open position, the cables 72 are oriented at approximately a45 degree angle relative to the ground. As the stroller 10 transitionsto the closed position, the fixed ends of the cables 72 are broughttogether such that, when the stroller 10 is in the closed position, thecables 72 are substantially parallel. In this way, the bag 70 does notcollapse as the stroller 10 transitions between the open and closedpositions.

With continued reference to FIGS. 1-9, in a non-limiting embodiment, thefront supports 20 of the stroller 10 are formed with a telescopingtube-in-tube design to reduce weight and improve overall appearance. Incertain other embodiments of the stroller 10, rather than a telescopingtube-in-tube design, the front support 20 could be constructed as anon-coaxial tube with an external telescoping guide, as is known in theart.

In a tube-in-tube configuration, the front support 20 includes an innertube 52 and a hollow outer tube 54. The outer tube 54 extends from anend of the front support 20 to the frame joint 24. In the embodiment ofthe stroller 10, depicted in FIGS. 1-9, the outer tube 54 is positionedat the lower portion of the front support 20, and the inner tube 52 ispositioned at the upper portion of the front support 20. However, it isunderstood that this configuration may be reversed, such that the outertube 54 is positioned at the upper portion of the stroller 10. The outertube 54 includes a longitudinal slot extending, at least partially,along the length of the outer tube 54. The slideable joint 40 of thescissor linkage 18 is configured to be received within the slot 56.

Generally, a tube 54 having a longitudinal slot 56 would lack rigidityunless additional stiffening structures are disposed within the tube tocontribute additional structural stability. Accordingly, if noadditional structural members were included in the outer tube 54, whenthe stroller 10 is pushed with substantial force, the front supports 20may bend or flex causing the stroller 10 to feel unstable or poorlymade. However, inserting additional structural supports into the outertube 54 is difficult because the inner tube 52 is configured to insertfarther within the outer tube 54 as the stroller 10 transitions to theclosed position. Thus, there is limited space in the outer tube 54 forincluding additional structural supports.

With reference to FIGS. 10 and 11, to counteract this lack of rigidity,the stroller 10 includes an inner tube assembly 51 consisting of theinner tube 52 which is inserted partially within the outer tube 54, atube stiffener 80, and an extension member 82 extending between an endof the inner tube 52 and the tube stiffener 80. The inner tube 52 isinserted within the outer tube 54 approximately 5 to 6 inches when thestroller is in the open position and is configured to insert fartherinto the outer tube 54 as the stroller transitions to the closedposition. The tube stiffener 80 is a substantially hollow memberdisposed within the outer tube 54 below the slideable joint 40 when thefront support 20 is in the open position. The tube stiffener 80 includesa slot 84 which corresponds with the slot 56 of the outer tube 54. Thetube stiffener 80 provides rigidity for the lower portion of the outertube 54. When the stroller is in the open position, the extension member82 extends from an end of the inner tube 52 to the slideable joint 40.As the stroller 10 transitions from the open position to the closedposition, the extension member 82 pushes on the slideable joint 40advancing the joint 40 downward through the slot 56 of the outer tube 54and the corresponding slot 84 of the tube stiffener 80. As the extensionmember 82 is advanced downward, the extension member 82 is also receivedwithin the slot of the tube stiffener 80.

As shown in FIG. 11, the tube stiffener 80 may further include a portionhaving an unbroken sidewall 86 defining an entirely enclosed portion 88.The slot 84 is separate from the enclosed portion 88. As describedabove, an unbroken tubular member has increased rigidity compared to amember having a slot. By including the unbroken enclosed portion 88, therigidity of the tube stiffener is enhanced. Alternatively, the tubestiffener 80 could include a cross member extending longitudinally alongthe hollow interior of the tube. The cross member would contributerigidity to the tube stiffener 80. However, including a cross memberextending along the entire length of the tube stiffener 80 would addadditional weight.

In this configuration, it is understood that the outer tube 54 iseffectively divided into three segments when the stroller 10 is in theopen position. The first segment is the portion of the tube 54 betweenthe front wheels 46 and the slideable joint 40. The tube stiffener 80 isdisposed within this segment and contributes additional rigidity to thissegment of the outer tube 54. The second segment is the portion of theouter tube 54 from the slideable joint 40 to the inserted end of theinner tube 52. This segment of the outer tube 54 lacks rigidity sincethe only additional structure in this segment of the outer tube 54 isthe extension member 82. However, the rigidity of the other segments ofthe outer tube 54 has been found to be sufficient to ensure properfunction of the stroller 10 even though this middle segment lacksrigidity. The third segment corresponds to the 5 to 6 inches of overlapbetween the inner tube 52 and the outer tube 54. In this segment, theinner tube 52 provides additional rigidity for the outer tube 54.

Alternatively, the slot 56 of the outer tube 54 could be manufactured toextend only along the portion of the outer tube 54 between the slideablejoint 40 and lower end of the outer tube 54 (e.g., the portion of theouter tube 54 which includes the tube stiffener 80). In that way, therigidity of the second segment of the outer tube 54 would be preservedsince it would not include a slot 56. However, machining a slotextending only partially along the length of the outer tube 54 is moreexpensive than is machining a slot 56 along the entire length of theouter tube 54.

In a non-limiting embodiment of the inner tube assembly 51, theslideable joint 40 includes a key, which functions as a lockingstructure for the outer tube 54. The key is inserted into the slot 56 ofthe outer tube 54. The rigid member 38 of the scissor linkage 18 isconnected to the key to form the slideable joint 40. In thisconfiguration, the slidable joint 40 is freely rotatable, relative tothe key, along both the horizontal and vertical axis. When the stroller10 is in the open position, the key provides additional rigidity for theouter tube 54, helping to prevent the middle segment of the other tubefrom flexing or twisting during use. As the stroller 10 transitions tothe closed position, the key slides downward along the slot 56 as therigid members 38 are being rotated together about the center joint 42.Thus, the slideable joint 40 must freely rotate to accommodate both thedownward motion of the key and the horizontal rotation of the rigidmember 38.

With reference again to FIGS. 1-9, the stroller 10 further includes oneor more drive systems (e.g., an electric motor, hydraulic system, ormanually operable mechanical system) for transitioning the stroller 10between the open and closed positions. In one non-limiting embodiment,the stroller includes two driving subsystems, namely, a system fortransitioning the frames 12, 14 between the open and closed positions,and a system for latching and folding the parallelogram linkage 16.

The drive system for the frame consists of a drive mechanism 58 coupledto the front support 20. The drive mechanism 58 transitions the right 12and/or left frame 14 between the open and closed positions by insertingor removing the inner tube 52 from the outer tube 54. With reference toFIG. 13, the drive mechanism 58 includes a cable drive 112 coupled to afirst spool 114 and a second spool 116. It is understood that the spools114, 116 may be separate structures or integrally formed. A first cable118 and a second cable 120 are connected to the spools 114, 116. Thefirst cable 118 and the second cable 120 are disposed within the hollowportion of the front support 20 and extend longitudinally along thelength of the front support 20 from the frame joint 24 toward the upperend of the front support 20. The spools 114, 116 are configured suchthat when the first spool 114 is full, the second spool 116 is empty.Accordingly, when the stroller 10 transitions from the open position tothe closed position, one spool is rotated to release the cable while theother spool winds the cable inward. In this way, the drive mechanism 58pulls on the inner tube 52 to effectuate the transition to the closedposition. When the stroller 10 is transitioned to the open position, theprocess is reversed, meaning that the spool which received the cablewhen closing the stroller releases the cable when opening and viceversa.

In one preferred non-limiting embodiment, the cable drive 112 isdirectly connected to the first spool 114 and the second spool 116 suchthat a single revolution of the cable drive 112 causes a single rotationof the spools 114, 116. In such a configuration, it is necessary thatthe spools 114, 116 have a narrow diameter so that only a small amountof cable is drawn in or released by each successive revolution of thecable drive 112. Accordingly, a narrow gauge cable must also be used tofit on the narrow spool. It has been determined that cables formed fromsynthetic polymers such as ultra high molecular weight polyethylene(UHMWPE) form an effective thin cable having good mechanical strength.Connecting the cable drive 112 directly to the spindle reduces theweight of the drive mechanism 58 by reducing the number of parts.Alternatively, the cable drive 112 may be connected to the spools 114,116 through a gear box (not shown). The gear box permits slowerrevolution of the spools 114, 116, which permits use of a largerdiameter spool and cable. However, adding a gear box to the drivemechanism 58 increases the total weight of the system.

With reference to FIG. 14, the present invention recognizes that fordrive mechanisms 58 having narrow spools 114, 116, the difference in theamount of cable wound or unwound by each revolution of the spindle issubstantially different based on whether the spool is fully loaded orempty. Therefore, in the cable drive system of the present invention, inwhich, at the beginning of the transition from closed position to theopen position, one spool is empty and one is full, the amount of thecable being wound by one spool is substantially different from theamount of cable being unwound on the other spool. The discrepancybetween the amount of cable being wound and unwound means that one cablewill have excess slack when the drive mechanism is engaged. The excessslack could cause the cable to tangle during winding. To counteract thisdifference in the amount of cable being released, the drive systemfurther includes a first biasing member, such as a first spring 122, andsecond biasing member, such as a second spring 124, connected in serieswith the first cable 118 and the second cable 120 and anchored to anupper portion of the front support 20. The springs 122, 124 removeexcess slack from the cables 118, 120. In one non-limiting embodiment,the springs 122, 124 are in the extended position when the stroller 10is open and closed. However, during the transition, while the drivemechanism 58 is engaged, the biasing members 118, 120 compresslongitudinally toward the upper portion of the front support 20, therebyremoving any slack in the cables 118, 120.

In the above described embodiment of the stroller 10 and drive mechanism58, the stroller 10 includes only one drive mechanism 58 coupled to thefront support 20. A single drive mechanism can be used as long as thestroller 10 is sufficiently rigid so that movement of one front support20 causes corresponding parallel movement of the opposing front support20. Alternatively, the stroller 10 may include a drive mechanism 58coupled to each of the front supports 20. In that case, the drivemechanisms 58 may be configured to operate concurrently to synchronizemovement (e.g., opening or closing) of the right frame 12 and the leftframe 14.

With reference to FIGS. 15-16, the stroller 10 may further include adrive mechanism 60 coupled to the parallelogram linkage 16 fortransitioning the horizontal members 26, 28 of the parallelogram linkage16 from the extended position (when the stroller 10 is in the openposition) to the folded position (when the stroller 10 is in the closedposition). The drive mechanism 60 should also function as a latch orlocking member for maintaining the parallelogram linkage 16 in the openposition. In a preferred non-limiting embodiment, the drive mechanism 60is driven by an electric motor; however, other drive mechanisms as areknown in the art (mechanical, hydraulic, etc.) may also be used withinthe scope of the invention.

With specific reference to FIG. 16, in one non-limiting embodiment, thedrive mechanism 60 includes a screw drive 212 coupled to a rotatablegear 214. Rotation of the gear 214 drives a locking support element 216which is connected between the gear 214 and the folding joint 34 of thelower horizontal member 28. When the parallelogram linkage 16 is in theopen (e.g., extended) position, the locking support element 216 is alatch for preventing the horizontal members 26, 28 from folding. Morespecifically, in the open position, the locking support element 216 isapproximately singular (i.e., in alignment) with an axis 218 of the gear214 to effectively counteract any upward or downward force applied tothe horizontal members 26, 28. However, the drive mechanism 60 isconfigured so that the gear 214 and locking support element 216 arestopped just short (e.g., approximately 10 degrees short) of thesingular (i.e. aligned) position. Stopping rotation of the gear 214short of the singular position ensures that the gear 214 will not beaccidently rotated past the singular position. Since the drive mechanism60 cannot be driven backwards, if the gear 214 were accidently advancedpast the singular position, the transition between the closed and openposition would need to be repeated to lock the horizontal member 26 inplace. It has been determined that maintaining the locking supportelement 216 in an approximately singular position (within 10 degrees ofsingular) is sufficient to counteract folding forces and to effectivelymaintain and lock the parallelogram linkage 16 in the open position.

With continued reference to FIG. 16, in one non-limiting embodiment, thedrive mechanism 60 further includes a manual override clutch fortransitioning the drive mechanism 60 from an automatically foldingconfiguration to a manually folding configuration. The manual clutchincludes a lever 220 coupled to a rotatable cam 222. In the engaged(i.e., automatic) configuration, the lever 220 orients the cam 222 toexert a downward force on the screw drive 212 to maintain contactbetween the screw drive 212 and gear 214. A spring 224 also coupled tothe cam 222 provides additional downward force for maintaining thecontact between the screw drive 212 and gear 214. When the lever 220 isreleased (i.e., transitioned to the manual position), the cam 222rotates, thereby disengaging the screw drive 212 from the gear 214. Whenthe screw drive 212 is disengaged from the gear 214, the user canmanually fold the stroller 10 by applying downward force to thehorizontal members 26, 28.

A potential problem with a screw drive 212 which is configured to engageand disengage with a gear 214 is aligning the threads 226 of the screwdrive 212 with the teeth 228 of the gear 214. If the threads 226 andteeth 228 are not aligned when contact between the gear 214 and screwdrive 212 is established, the possibility exists that the threads 226will be pressed against the upper portion of the gear teeth 228, ratherthan into the gear 214, causing damage to the teeth 228 and/or threads226. In a preferred embodiment, the drive mechanism 60 prevents damageto the teeth 228 and gears 214 by initially applying a light preload andslowly rotating the screw drive 212 until the gear teeth 228 and threads226 of the screw drive 212 catch and align. Once the gear 214 andthreads 226 are correctly aligned, additional compressive force betweenthe screw drive 212 and gear 214 is applied and the rotation speed ofthe screw drive 212 is increased. However, the gears 214 and screw drive212 are not subjected to this additional force until it is determinedthat the screw thread 226 and gear 214 are aligned. In certainembodiments, the drive mechanism 60 further comprises a sensor (notshown) for determining whether the screw drive 212 and the teeth 228 ofthe gear 214 are correctly aligned. If the sensor determines that thealignment is correct, there is no need to apply the light preload forcefor aligning the gear 214. If the sensor determines that the gear 214 isnot in alignment, the light preload is applied. In an alternativeembodiment, the drive mechanism 60 does not include an alignment sensor.In that case, the preload pressure will be applied each time that thegear 214 is brought into contact with the screw drive 212, whether ornot they are in alignment.

The drive mechanism 60 may further include a visual indicator (notshown) such as a display, switch, or lighted button for informing theuser about what position the drive system is in. For example, the visualindicator could indicate three possible stages: auto, in which the gear214 and screw drive 212 are engaged and locked together such that fullpower can be applied to open or close the stroller 10; manual, in whichthe gear 214 and screw drive 212 are not engaged allowing users tomanually open or close the stroller 10; or auto but disengaged, in whichthe gear 214 is not properly aligned and light pressure will be appliedto align the gear 214. Alternatively, the position of the lever 220 maybe sufficient to indicate to a user whether the clutch is in theautomatic or manual position.

The present invention also recognizes the possibility that a user maytry to force the stroller 10 to close while the drive mechanism is inthe automatic position and the gear 214 is engaged with the screw drive212. Such forcing motion would potentially strip the gear 214 damagingthe driving mechanism 60. To counteract such forcing motion, in onepreferred embodiment, the drive mechanism 60 is configured toautomatically transition from the engaged to disengaged position.Specifically, when a user applies substantial downward force to thehorizontal members 26, 28, the cam 222 will rotate, thereby disengagingthe screw drive 212 from the gear 214.

With reference to FIGS. 13 and 15, the drive mechanisms 58, 60 furtherinclude a synchronizing connection between the frame drive mechanism 58and the parallelogram drive mechanism 60 to ensure that the frame drivemechanism 58 will not engage when the parallelogram drive mechanism 60is in the manual (i.e., disengaged) position. In one non-limitingembodiment, the connection 230 includes a rotatable cam 232 coupled withthe parallelogram drive mechanism 60 which is in mechanical connectionwith a corresponding rotatable cam 126 of the frame drive system 58through a cable 230. When the parallelogram drive mechanism 60transitions from the engaged position to the disengaged (i.e., themanual) position, the cam 232 rotates causing the corresponding cam 126of the frame drive mechanism 58, which is connected by the cable 230, torotate. Rotation of the cam 126 of the frame drive mechanism 58 causesthe cable drive 112 to disengage from the spools 114, 116 to preventrotation. When the parallelogram drive mechanism 60 is transitioned tothe automatic position, the cam 126 of the frame drive mechanism 58 isrotated to reinitiate connection between the spools 114, 116 and cabledrive 112 to permit folding movement of the front support 20.

In addition to the above described drive mechanisms 58, 60, the stroller10 may include numerous other electrical systems within the scope of thepresent invention. For example, the stroller 10 may include headlights,daytime running lights, as well as a user interface system. Several userinterface options are provided within the scope of the present inventionranging from a simple interface to a complete interface offeringinformation about the stroller 10 and surrounding environment. Withreference to FIGS. 17-18, in one embodiment, the user interface ispresented on a LCD visual display 62 disposed on an end of the handles44 of the stroller 10. An exemplary schematic drawing of a visualinterface 62 in accordance with the present invention is depicted inFIG. 18. The visual interface 62 displays information from the pluralityof sensors on the stroller 10 including speed, baby on board, open orclosed, as well as, temperature, total distance traveled, and time, aswell as other relevant information important to a user.

In one non-limiting embodiment, the electronics systems of the stroller10 are powered by an on-board battery that is charged as the stroller ispushed. In certain embodiments, this charging is accomplished bygenerators housed in the stroller wheels 46, 48 combined with circuitryused to direct the power generated by the stroller 10 back into thebattery. An exemplary generator for use with a power folding stroller isdisclosed in U.S. Pat. No. 8,193,650, issued on Jun. 5, 2012, which ishereby incorporated by reference in its entirety. Optionally, thestroller may also be charged via an AC adapter, such as a wall adapter.

In one non-limiting embodiment, the above described electronics (e.g.,drive mechanisms, sensors, headlights, visual displays, and odometers)are controlled by one or more microcontrollers. Although all control canbe handled by a single microcontroller, it is sometimes advantageous touse multiple microcontrollers for a cost advantage. For example, one ormore microcontrollers are used to control and monitor the variouselectronic components associated with power folding and unfolding. Inone preferred embodiment, the drive mechanisms are controlled viaseveral of the microcontroller ports which in turn control the motordrive electronics. In one embodiment, the motor drive electronicsconsist of an H-bridge style circuit allowing the motors to be run in abi-directional manner and at various speeds via pulse-width modulation(PWM). The microcontroller may utilize several addition ports to monitorvarious sensors which provide information about the position of theframe, the position of the latch, and whether the stroller 10 has achild onboard. Remaining microcontroller ports are dedicated to a userinterface of the stroller 10, which provides a means for the user tointeract with the stroller 10 and where the stroller 10 communicatesinformation to the user.

In certain configurations, the various electronic components of thestroller 10 are controlled by software systems responsible for utilizingthe electrical system to manipulate the mechanical system in a safe andefficient manner. Sensors contained in the electrical system are routedback from the microcontroller which contains the software used toprocess the sensors data and determine an appropriate action. There arethree major sections to the software.

The first section handles the user interface where information iscommunicated to the user regarding the state of the stroller'smechanical and electrical systems, and where the user can interface withthe stroller 10, for example, to request the stroller 10 to fold orunfold. The second section handles monitoring the state or condition ofthe stroller 10. The software will interpret the various signalsreceived from the sensors and determine whether the stroller 10 is in auseable state (e.g., mechanically and structurally sound), whether thestroller 10 is occupied, whether the stroller 10 is broken, etc. Thethird section handles the motion of the stroller 10 through the foldingand unfolding process. Throughout the folding and unfolding process, thesoftware must monitor various safety protocols to protect the occupant,the user, and the mechanics.

In one embodiment, the software for controlling folding and unfoldingcomprises an activation sequence controlled through an activation switch64. The activation sequence may include obtaining information from oneor more object sensors having the ability to detect the presence ofobjects within the interior portion of the stroller 10 and to interruptand/or prevent movement of the stroller 10 in the direction toward itscollapsed condition when the object sensor detects the presence of anobject within the interior portion of the stroller 10. The object sensoror sensors may be of any known type such as a mechanical weight sensor,a proximity sensor, a motion sensor, a light beam sensor, or any otherdevice having the ability to detect the presence of an object within theinterior of the stroller 10. The sensor or sensors may be electronic andmay send a signal that is electrically acted upon to prevent orinterrupt power to the motor, and/or the sensors may be mechanical andactuate a physical lock or a brake to prevent further collapsing or thefull collapsing movement of the stroller 10. Sensors may also be used todetect the presence of modular add-on devices connected to the stroller10, such that movement of the stroller 10 to its collapsed condition isprevented when a connected add-on is detected, thereby preventingpotential damage to the add-on device.

In a preferred embodiment, the activation switch 64 is a dead man switchdisposed on the handles 44 of the stroller 10. A dead man switch must beengaged (i.e., pressed downward) throughout the entire opening orclosing movement. Releasing the switch pauses the folding or unfoldingmovement of the stroller 10. Pressing the switch a second time continuesthe movement. The switch may further include a twisting element 66 forpriming the activation sequence prior to initiating the opening orclosing action.

With reference to FIG. 19, a non-limiting embodiment of the activationsequence for the stroller 10 is depicted. As indicated in the exemplaryactivation sequence, at most times, the stroller 10 control unit isidle. Engagement of a twisting element 66 or dial primes the controlunit, essentially waking it up from idle. The activation switch 64 mayinclude an indicator, such as a sound or light, that demonstrates thatthe control unit has transitioned from idle to primed. After priming,the user initiates activation (opening or closing the stroller 10) bypressing the activation switch. In certain embodiments, the unit willonly remain primed for a limited time period, after which, the unit will“timeout”. At that point, the unit may include means to inform the userthat the priming has timed out and the unit is returning to idle. Whenthe activation switch 64 is engaged (i.e., depressed), the unit isconfigured to receive and evaluate safety data from a plurality ofsafety sensors disposed on the stroller 10. Relevant safety dataincludes whether a child is present, whether the clutch is in the manualposition, and the battery level of the power supply. The stroller 10 mayalso monitor external conditions such as whether the stroller isconnected to an external power source, in which case folding orunfolding may be prevented. In certain embodiments, the stroller mayalert the user of unsafe conditions such as by describing the conditionon a visual display 62. If the sensors indicate that the stroller 10 issafe to fold or unfold, the folding movement is started or resumed.Folding continues until folding is complete or until the activationswitch 64 is released to pause the folding process. When folding ispaused, the unit remains primed until either the button is pressed toresume folding or until the unit times out and returns to idle.

The software further includes a frame folding sequence integrated withsensors for determining frame position. The position sensors utilized atselective locations on the frame to send a signal indicative of thepositions of one or more components or elements of the stroller 10. Theposition sensors can be used for several purposes, such as sending asignal to the display to provide a visual and/or audio indication to theuser as to the current position or of the deployment or the collapsingof the stroller 10, and/or to provide an interrupting signal (ornon-signal) if a position sensor or sensors are not engaged as theywould be during proper deployment and/or collapsing of the stroller 10.Any one or more of several known types of sensors may be utilized, suchas rotary encoders at any one or more frame component pivot points,and/or limit or contact switches which are engaged as selective elementsof the stroller 10 move to their proper positions, or improperpositions, during deployment and/or collapsing of the stroller 10. Byway of example, position sensors may be mounted to the stroller 10 atpositions which provide indication that the stroller 10 has moved to itsfully-deployed condition, its fully-collapsed condition, or anycondition in-between; and/or position sensors may be mounted atlocations to detect the engagement or lack of engagement of latches.Position sensors may operate in conjunction with electronic timercontrols such that a signal to effect stoppage of power to the motor issent if the position sensor is not engaged within a predetermined timeperiod.

With reference to FIG. 20, in one preferred and non-limiting embodiment,the frame folding process begins by receiving information about whetherthe unit power is on, whether the manual clutch override is engaged, andwhether the wall charger is plugged in. The unit controller must beturned on during folding. However, folding is prevented when the clutchis in the manual position and when the stroller is plugged into a wallcharger. When folding is activated by pressing the activation button,the unit receives information from a plurality of frame sensorsincluding the status of the parallelogram linkage 16 (latched orunlatched), the location of the sliding joint 40 (down or up), orwhether the telescoping tube is extended or nested. The information fromthe frame sensors is used to determine whether the stroller 10 is in theopen or closed, position. Based on the information, actuation of thestroller 10 open or stroller 10 close functionality occurs. Duringactuation, the unit continues to monitor the frame sensors to determinewhen opening or closing is complete. If folding or unfolding iscompleted, the user is notified that the action was successful.Otherwise, the user is alerted that a folding error occurred. It isnoted that, as described with regard to the activation sequence, theuser can pause folding by releasing the dead man switch. Folding isresumed by pressing the switch to continue folding or unfoldingactuation. If the unit remains paused for a period of time, foldingtimes out and the unit returns to the idle or stop folding positionuntil the user reactivates the system by priming the activation switch.

Although a collapsible stroller 10 has been described in detail for thepurpose of illustration, it will be appreciated by those skilled in theart that various modifications and alternatives to those details couldbe developed in light of the overall teachings of the disclosure.Accordingly, the particular arrangements disclosed are meant to beillustrative only and not limiting as to the scope of invention which isto be given the full breadth of the claims appended and any and allequivalents thereof. Further, although the invention has been describedin detail for the purpose of illustration based on what is currentlyconsidered to be the most practical and preferred embodiments, it is tobe understood that such detail is solely for that purpose and that theinvention is not limited to the disclosed embodiments, but, on thecontrary, is intended to cover modifications and equivalent arrangementsthat are within the spirit and scope of the appended claims. Forexample, it is to be understood that the present invention contemplatesthat, to the extent possible, one or more features of any embodiment canbe combined with one or more features of any other embodiment.

The invention claimed is:
 1. A stroller comprising: a frame; and a drivemechanism coupled to the frame and configured to transition the framebetween an open position and a closed position, the drive mechanismcomprising: a cable drive; at least one spool rotated by the cabledrive; and at least one cable having a first end received by the atleast one spool and a second end connected to the frame.
 2. The strollerof claim 1, wherein rotation of the at least one spool by the cabledrive causes the cable to exert a force against the frame to transitionthe frame between the open position and the closed position or betweenthe closed position and the open position.
 3. The stroller of claim 1,wherein the frame comprises at least one telescoping tube, thetelescoping tube comprising: an outer tube; and an inner tube slidablyinserted in the outer tube, wherein the inner tube is retracted withinthe outer tube as the stroller transitions from the open position to theclosed position and is extended from the outer tube as the strollertransitions from the closed position to the open position.
 4. Thestroller of claim 3, wherein the cable exerts a force against the innertube to draw the inner tube into the outer tube.
 5. The stroller ofclaim 3, wherein the cable extends at least partially through a hollowportion of the inner tube or a hollow portion of the outer tube.
 6. Thestroller of claim 1, wherein the cable drive is in direct rotationalconnection with the at least one spool.
 7. The stroller of claim 1,wherein the cable comprises a synthetic polymer.
 8. The stroller ofclaim 1, further comprising an activation button for actuating the drivemechanism to transition the stroller from the open position to theclosed position or from the closed position to the open position.
 9. Thestroller of claim 8, wherein the activation button is a dead man switch.10. The stroller of claim 1, wherein the at least one biasing membercomprises a spring.
 11. The stroller of claim 1, wherein the drivemechanism comprises a first spool that receives a first cable and asecond spool that receives a second cable.
 12. The stroller of claim 11,wherein rotation of the first spool and the second spool by the cabledrive causes the first spool to wind the first cable and the secondspool to simultaneously unwind the second cable.
 13. The stroller ofclaim 1, further comprising a foot stand connected to the frame andconfigured to maintain the stroller in an upright orientation when thestroller is in the closed position.
 14. A stroller comprising: a framecomprising a right frame portion and a left frame portion, each frameportion comprising a front support rotatably connected to a rear supportat a frame joint; and a drive mechanism coupled to the frame andconfigured to transition the frame between an open position and a closedposition by rotating the front support relative to the rear support, thedrive mechanism comprising: a cable drive; at least one spool rotated bythe cable drive; and at least one cable having a first end received bythe at least one spool and a second end connected to the front support,the at least one cable extending through at least a portion of the frontsupport.
 15. The stroller of claim 14, wherein rotation of the at leastone spool by the cable drive causes the cable to exert a force againstthe portion of the front support, thereby transitioning the framebetween the open position and the closed position or between the closedposition and the open position.
 16. The stroller of claim 14, whereinthe cable drive is in direct rotational connection with the at least onespool.
 17. A stroller comprising: a frame; and a drive mechanism coupledto the frame and configured to transition the frame between an openposition and a closed position, the drive mechanism comprising: a cabledrive; at least one spool rotated by the cable drive; a first cablehaving a first end received by the at least one spool and a second endconnected to a first portion of the frame; and a second cable having afirst end received by the at least one spool and a second end connectedto a second portion of the frame, wherein rotation of the at least onespool by the cable drive winds the first cable and simultaneouslyunwinds the second cable, thereby transitioning the frame from the openposition to the closed position or from the closed position to the openposition.
 18. The stroller of claim 17, wherein the drive mechanismfurther comprises: a first biasing member connected in series betweenthe second end of the first cable and the first portion of the frame,thereby connecting the second end of the first cable to the firstportion of the frame; and a second biasing member connected in seriesbetween the second end of the second cable and the second portion of theframe, thereby connecting the second end of the second cable to thesecond portion of the frame.
 19. The stroller of claim 17, wherein theat least one spool is in direct rotational connection with the cabledrive.
 20. The stroller of claim 1, wherein the drive mechanism furthercomprises at least one biasing member connected in series between thesecond end of the at least one cable and the frame, thereby connectingthe at least one cable to the frame.
 21. The stroller of claim 14,wherein the drive mechanism further comprises at least one biasingmember connected in series between the second end of the at least onecable and the front support, thereby connecting the at least one cableto the front support.